18 MINUTES OF 



Oh the component Principks-of Fegetables. 



%dncli CQiwtaiitly possess that form intke temperature of our climates; such as the • 

 butro- of cacao, wax, and pita ef the Chinese. 



If the nuclei of mlmonds, walnuts, olives, linseed, rapeseed, hempseed, the 

 seeds of the popp^, tocoai and those of the ricitius or castor-oil tree, be expressed, 

 an unguinous oil is extracted' The manner h\ which the oil is generally obtained, 

 is'W'ftrttrCrushing the seed between krge stones, into a kind of paste; which is 

 put into bags and squeezed in a press : the oil is thus forced out of the seed, and 

 received in a proper vessel. 



Some of these contain also a bitter or narcotic material, as bitter almonds, a- 

 pricot kernels, acorns, hors§-chesnuts; which, as it adheres to the mucilage, may 

 be separated from the oil ; as in expressing the oil from bitter almonds, which is 

 as sdod as from sweet ones. s 



2. Concerning volatile Oils. 

 Fixed oil is combined with mucilage, volatile oil with the spiritus rector, 

 or aroma; and it is this combination or mixture which constitutes the.differencc 

 betAveen them. The volatile oils are characterized by a strong smell, more or less 

 agreeable; they are soluble in alcohol, and have a penetrating and acrid taste. 

 All the aromatic plants contain volatile oil, excepting those whose smell is very 

 transient, such as, jasmin, 'violets, lilies, &c. 



By distillation, plants give over with the water, a quantity of volatile oil, 

 which floats 0n the top in small globules. 



Volatile or ethereal oz7 resides in a particular appropriated part of the 

 plant; thus it is only found in the corollaceous petals of the rose, chamomile, jas- 

 mine and hyacinth; in the stigmata of the crocus sativus, called saffron; in the 

 calyx of the clove-tree; in the leaves oimint, balm, sage and savine; in the root of 

 valerian, sweet smelling rush, and angelica; in the cortex of the cascarilla tree; 

 in thelibej: of the cinnamon tree; in the epidermis of the cassia tree; in the wood 

 'of sassafras and yelloxo saunders; in the whole fruit or berries o^ the juniper tree 

 snd laurel; in the bark of the fruit of the lemon and orange trees; in the pellicle 



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